1. Field of the Invention
The present invention relates generally to a signal recording and reproducing method, and a storage medium processor. The present invention relates, more particularly, to the signal recording and reproducing method, and a storage medium processor wherein signal storing means for temporarily storing a signal is provided and a movable area boundary point is set in the signal storing means so that a first area for storing a signal to be recorded on a storage medium and a second area for storing a signal reproduced from the storage medium are provided, signals read by prefetching the signals when the storage medium processor is in a signal readable state are stored in the second area, signals supplied before the storage medium processor becomes a signal recordable state are stored in the first area and further, responsibility in a signal recording and reproducing operation is enhanced efficiently utilizing the signal storing means by moving the area boundary point and varying the areas.
2. Description of Related Art
In a computer system, information is generally stored using a storage medium enabling random access, for example, a disc-type storage medium such as a magneto-optical disc. As for a magneto-optical disc, a floating magnetic head or a contact type magnetic head as adopted in a hard disk drive using a magnetic disk is used in place of a fixed magnetic head to enhance its recording density.
When the above floating magnetic head or the above contact type magnetic head is used, a magnetic head driving mechanism for lifting or lowering the magnetic head is provided. When magneto-optical disc is replaced, the magnetic head driving mechanism has to move the magnetic head in a position apart from the magneto-optical disc. However, it takes much time to move the magnetic head, and then a signal cannot be promptly written or read.
The object of the present invention is to provide a signal recording and reproducing method, and a storage medium processor by which a data signal can be promptly read or written and which enables a computer to process a data signal stored on a storage medium.
In carrying out the invention in one preferred mode, I provide a signal recording and reproducing method wherein signal storing means for temporarily storing a signal is provided and a signal to be recorded on a storage medium or a signal reproduced from a storage medium is stored on the signal storing means. The method comprises setting a movable area boundary point in the signal storing means to form a first area for storing a signal to be stored on the storage medium and a second area for storing a signal reproduced from the storage medium, recording a signal stored on the first area in the storage medium and acquiring a signal to be reproduced on the basis of a signal stored on the second area.
As another preferred mode, I provide a storage medium processor comprising signal recording means for recording a signal on a storage medium, signal reproducing means for reproducing a signal recorded on the storage medium, signal storing means for temporarily storing a signal and control means for controlling the signal recording means, the signal reproducing means and the signal storing means. The control means sets a movable area boundary point in the signal storing means in which a first area for storing a signal to be recorded on the storage medium and a second area for storing a signal reproduced from the storage medium are provided.
In the present invention, the signal storing means for temporarily storing a signal, for example, a buffer memory is provided and a pointer, which is a movable area boundary point, is set in the buffer memory. According to the above pointer, the first area for storing a signal to be recorded on a storage medium and the second area for storing a signal reproduced from the storage medium are provided. When a storage medium is installed and a signal is able to be read therefrom, a prefetched signal is stored in the second area and afterward, a signal to be recorded on the storage medium supplied before a signal is recorded on the storage medium is stored in the first area.
When the first area has a space area or when a signal stored in the first area is recorded on a storage medium and a space area is generated, the pointer is moved and the second area is expanded. Also, when the pointer is moved and the second area is expanded up to the maximum limit, a signal recorded on a storage medium are prefetched and the prefetched signal is stored in this area.
In the signal readable state, a signal to be recorded on a storage medium can be input and afterward, when a signal to be recorded on the storage medium is supplied before a signal is recorded on the storage medium, the above signal is stored in the first area. The pointer is moved according to the quantity of supplied signals and the first area is expanded.
When an alternate area is provided to the storage medium, a third area for storing a signal on the alternate area is provided. Further, when a storage medium is a read only memory, the first area of the signal storing means is used for the second area thereof.
A further understanding of the nature and advantages of the invention may be realized by reference to the following portions of the specification and drawings.